php 获取ip地址的5种方法，插入用户登录日志实例

php 获取ip地址的5种方法，插入用户登录日志实例，推荐使用第二种方法

<?php   //方法1：
$ip = $_SERVER["REMOTE_ADDR"];
echo $ip;

//方法2：
$ip = ($_SERVER["HTTP_VIA"]) ? $_SERVER["HTTP_X_FORWARDED_FOR"] : $_SERVER["REMOTE_ADDR"];
$ip = ($ip) ? $ip : $_SERVER["REMOTE_ADDR"];
echo $ip;

//方法3：
function getRealIp()
{
    $ip=false;
    if(!empty($_SERVER["HTTP_CLIENT_IP"])){
        $ip = $_SERVER["HTTP_CLIENT_IP"];
    }
    if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
        $ips = explode (", ", $_SERVER['HTTP_X_FORWARDED_FOR']);
        if ($ip) { array_unshift($ips, $ip); $ip = FALSE; }
        for ($i = 0; $i < count($ips); $i++) {
            if (!eregi ("^(10│172.16│192.168).", $ips[$i])) {
                $ip = $ips[$i];
                break;
            }
        }
    }
    return ($ip ? $ip : $_SERVER['REMOTE_ADDR']);
}
echo getRealIp();

//方法4：
if ($HTTP_SERVER_VARS["HTTP_X_FORWARDED_FOR"])
{
    $ip = $HTTP_SERVER_VARS["HTTP_X_FORWARDED_FOR"];
}
elseif ($HTTP_SERVER_VARS["HTTP_CLIENT_IP"])
{
    $ip = $HTTP_SERVER_VARS["HTTP_CLIENT_IP"];
}
elseif ($HTTP_SERVER_VARS["REMOTE_ADDR"])
{
    $ip = $HTTP_SERVER_VARS["REMOTE_ADDR"];
}
elseif (getenv("HTTP_X_FORWARDED_FOR"))
{
    $ip = getenv("HTTP_X_FORWARDED_FOR");
}
elseif (getenv("HTTP_CLIENT_IP"))
{
    $ip = getenv("HTTP_CLIENT_IP");
}
elseif (getenv("REMOTE_ADDR"))
{
    $ip = getenv("REMOTE_ADDR");
}
else
{
    $ip = "Unknown";
}
echo $ip ;

//方法5：
if(getenv('HTTP_CLIENT_IP')) {
    $onlineip = getenv('HTTP_CLIENT_IP');
} elseif(getenv('HTTP_X_FORWARDED_FOR')) {
    $onlineip = getenv('HTTP_X_FORWARDED_FOR');
} elseif(getenv('REMOTE_ADDR')) {
    $onlineip = getenv('REMOTE_ADDR');
} else {
    $onlineip = $HTTP_SERVER_VARS['REMOTE_ADDR'];
}
echo $onlineip;  

实例：在用户登录时获取用户IP，插入到数据库登录日志表里

//增加用户登录日志
                $ip = ($_SERVER["HTTP_VIA"]) ? $_SERVER["HTTP_X_FORWARDED_FOR"] : $_SERVER["REMOTE_ADDR"];
                $ip = ($ip) ? $ip : $_SERVER["REMOTE_ADDR"];
                $this->usermodel->addUserlog($userid,$nickname,$ip);

function addUserlog($userid,$nickname,$ip) {
        try {
            $now = date("Y-m-d H-i-s",time());
            $data=array(
                'userid'=>$userid,
                'nickname'=>$nickname,
                'ip'=>$ip,
                'logintime'=>$now
            );
            $insert_query = $this->db->insert_string('user_log', $data);
            $this->db->query($insert_query);
            return 0;
        } catch ( Exception $e ) {
            return -1;
        }
    }

日志表结构：

CREATE TABLE `user_log` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `userid` bigint(20) NOT NULL,
  `nickname` varchar(50) NOT NULL,
  `ip` varchar(50) NOT NULL,
  `logintime` datetime NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8